Eccentric equalizer for derricks



2 Sheets-Sheet l L. A. RAwsoN Filed Jan. I 23. 1951.

v[NM/5N To@ ESL/5 ,4. EA wsoA/ Aug. 9, 1932.

ECCENTRIC EQUALIZER FOR DERRICKS Alg- 9, 1932 L. A. RAwsoN 1,871,133

ECCENTRIC EQUALIZER FOR DERRICKS Filed Jan. 25. 1931 2 Sheets-Sheet 2#Trage/v5 Y.

Patented Aug. 9, 1932 onmnonnmgnssrenon 'roV nivrsoo DntannmACALIFORNIA.

Ecennmnio EQUALIZEn Fonnnnnmxs,

Application*ledalnuary', 1931: Serial Non 510;699.

This invention frelates to ia-iderriok.; oonf-y struction havingaebasestruotureeai crownr` structure, and aepluralityor":doublefleg-:coneA struetions extended froml the basetolthe: Crownstructure, and imeans cooperating beiv tweenthe:doublezlegioonstruetionsrandfone of? the structures forvproportioning the load-bee` tween the legs ofthedouble legconstructions;

The invention vlinds: its utility;` in the oil- ':f:. producingvindustry;V where double leg con:-A

lportions the load-so tha'tl take its shareolther-load,l andso-fthatthe'` auxiliarylegrwill take: the remaining :shareI ot;-

struction .derricks are; in use.v It is the vpraetice at the presentltime to providea tderrick with a main leg and fan auxiliary lor removeable leg, whioh'rernovable leg tis used during- -i drilling operationswhen .the loads imposed?V on the derriok are quiltexheavyeandisrernovedfi during pumping operations; when the? load fis relativelylight.y InuthepresentA derrieks;V

means is; providedffor `causing-the auxiliaryt if! leg 'to take aportion of the loadn on-the-dere.

rick, but :there is no lmeans for; automatically' prop ortioning the`load :between'the main andf';

auxiliary legs.t usually oeou-rs,- tha-tithe Ina-in and :auxiliary:rlegs fdo: not aassurneftheirl proper proportions of: the,load'Twitli"there-V sult that i there" isz-1 a ldangerrof inj uryz-toathfe f,

derrick.V

VIn the derrickiofinyfinventionthe equalize ingmeans which IeniployzautoInatioally,proa` the: main deg-wi'llzthe load-. Indesigningthe=,fderriclfotrnygimv ing pumping operations in thefwell; Theauxiliary 4leg is made strongienough'torsafely carry the differencebetweentheloads imi-' posed on the*I derriek the loadwill beproperly-distributed and'isof thatl neither leg V'will be subjected` togreateri Y .loads than `it is intended to support.

The form of equalizing ymeansrwhich constitutesl an element ofitlie`present combina f tion includes an eccentrio equallzmg-,mernberhavingieooentric portions engaging theomain and auxiliary ylegs ofthederrik,l and havingh4 ulerum; portions which engage- 1 ethieri the;

luring pumping and 'i the loads imposed on rthederriclr during fdrill.

ing; The equalizing means'is'sodesignedthata crown structure orbasestructure, depending i on whether-the equalizing means is placed in?ithe upperfpartxor the lowerpart of thederfh Theequali'zingsmeansofmypresentinveney tionf-is--quite rugged and has ample loearlngfAsurfaces for suppvortingethe loads imposed-on. v

thev derrie'k; v

Other@objeetsandvadvantages of theinventionA will b'emade evident inthefollowingy d eseription.y

Referring to the :drawingsin which-I illusf:

tratenry. inventiongf- Eig; l? isg anzelevational viewiof 1aderrie'lrrincorporating my invention, the central por@ tion" otn thederriek beingibroken away and the upperand-:lower parts movedtogethersin order1thatthefbaseA and'icrownof the; derrck.- y

may be :illustrated:

Elige-1 2 fls- :a: cross-section taken:y on-the line Eigrsarl-elevational vie-w -show-ing'one- Y ortlre1douloleleg:constructionsrwhich 1consti-`` tutes aspartofmyjinventi oni.;

Fig, 4 isflan enlarged elevational; view"` o the: equalizingfmeans.- v

Y Fig. buis: an enlarged elevational iviewg as;

indioatedbyz the arrow .5' of Fig; 4."

Fig: y(3l-is sectional view4 taken on :the line,

6 6 of'Fig. 4.

Egl,isaaperspeotivefview-:of the eecentrio eojiuafli-,zilrggg-` memberofthe invention.

Referrrngto Figs: Land 2 ofithefdrawings,

thennrneral; 11 represen-csi a *A baselstructurei Tfh'e numeral i12rrepresent-sra crownstructure.-`

The numeral 14represents double-legfconstructions',v andthe numeral 15jrepresentsftlier ingfto;usua1l; pra z'tice,l there-are fourdoubleA legoonstrnotion-sf147 onelof which -is arranged:

ingeaCb; :eornerfofA ther derrel.

Since eaoh fof! the :double leg construetions'y is .of 'the,sa1neydiameter, If will, in describing; the-details. off' Constructionthereof; refer-to 1asingle doublet, leg f oonstrnotion:A It should beunderstood,`

however; thatfthe.-descriptions applies to all? fourclbublelegeconstructions:of`tl1e1derriclnA i detailed construction ofthe double 'leg construction of the invention. The numeral 16 representsa. main leg or primary leg of the derrick. This primary lleg 16 ispreferably of angular cross-section and is secured at its lower end toa' corner piece'l7 lwhich constitutes a part of the base structure 11.`The upper end of the main leg 16 is secured to an equalizing means 18which constitutes a Ypart ofthe presentk invention and which will bedescribed in detail in the ensuing part of this' description. Thenumeral V2()1 represents anjr auxiliary or secondary leg which restskinside.A

the primary leg 16 and is vpreferablyof c ylinm-e` dricalycross-section, as shown bestl in Fig. 8.

Theisecondary leg is Vretained in place within the /primary leg 16` by`suitable .t'ying'meansV 21.A The lower Vend of the secondary leg is`provided .with a ball 22 which engagesa socket 23 provided Y-by theVcorner `piece-1.7.

nected to the equalizing means 1 Referring now particularly to Figs.Y 4toVV 7 inclusive, I will now describeindetail the Theupper end of the"secondary leg is con? equalizing-,means which, by itself and in com!bination with the other parts of the 'derricln constitutes thepresentinvention. The egualizing means includes an eccentric equalizmgmember 30 which has a pair of spaced fu-l- Interposed between thesefulcrum portions 31 isa secondary or central eccentric portion32 whichis arranged on an axis eccentric to the axis'von which the fulcrumportions 31 Vare disposed. The secondary or central eccentricl portion32 is cylindrical, as shown. Arranged outside and adjacent to thefulcruin portionsl v 31 are Aprimary ork outer eccentric portions 33which are relatively spaced but are in axialY alignment. The portions31, 32, and 33 are ,preferably formed on axes Vwhichare-relaleg 16' is avprimary bearing member 34 having flanges 35 which engage the externalfaces `of the primary leg 16 and thro-ugh which bolts 36 are extended.'``Arranged in spaced rela-V tion are'primary bearings 37 which` includeblockportions 38for1`ned integral with theA primary bearing member 34,.Caps 39 arel adapted to Vbe secured to the blocks 38 by,

suitable bolts '40.'v The' primary bearings 371 are in Vaxial alignmentand are of such a shape and size that theyjournal the primary eccentricportions 3.3 ofthe eccentricy equalizi'ng member'30. Sup-'ported' attheupper end ofY vthesecondary leg 20 is a secondary bearing member42'having acylindrical portion 43 adapted toextend inside` the secondaryleg 20 and having a'shoulder 43a with which the upper Vend of thesecondary leg V20 is in 'en-- gagement. The secondary bearing member Athe bolt 58 it may crum portions -3l which are in Vaxial align-` mentand whichare cylindrical, asV shownb crum axis 42 provides a secondarybearing which has a block 44 formed as an integral part of the bearingmember 42 anda cap 45 which is in n the form of'a U-shaped strap, andwhich is secured to the bearing bolts 46. These. parts are designed tojournal the secondary or central eccentric portion 32 of the eccentricequalizing member v30.

The crown. structure ofthe derrick includesahead-piece or body 49, oneof which of thederrick, and

tions and hold these portionsin proper operating relation with thefulcrum seats 52.

Extending outward from the primary bearing member 34is'a ange 57 throughwhich a` extended'. By rotating Y threaded bolt 58 is be advanced upwardVor downward and 'caused to engage or disengagef the. plate 50 Yof thehead-piece 49.

s shown best in ize'r member is 'aj means for vproportioning the loadVimposedf-on .the primary and sec-1r' ondary legs andhas a fulcrum axisaround-which the member 30 is.` adapted to fulcrum or swing. The themember 30 on an Z-Z.- The'line 'Y is spacedffrom .the fultanceB. Ifthedistances A and B" were equal,`the load imposed'on the primary'and Asecondary legs would. be equally divided'. It!

will be seen by changing thedesign ofthe member 30in'order to change thedistances A andB and 'to make one greater than the other, that one legof the double leg constructlonmcy be caused to carry a greater portionof the load. y f

'The threaded bolt 58V is intended for use when the auxiliary orsecondary leg 20 is eing installed or removed; At this time the Y bolt58 ,is advanced upward and caused to engage jthe hea.dpiece 49.The'liead-piece vis therebyl movedl equalizer member is pivoted aroundthe axis on which the'primary eccentric portions 33' are arranged asufficient distanc'eto raise the secondary or `central eccentric portionand the secondary bearmg'member 42 associated y therewith, to accomplisha disengagement bel' tween the cylindrical part 43 of the secondarybearing member 42 and the upper end of the member by suitable bolts 54,which straps extend around and below the fulcrum por- FigQG, theeccentric equal- X a distance A,'and the'lineZ is spaced away from thefulcrum line Xia dis.-

primary leg engages n' axisl Y-Y, and the. secondary leg engages themember 30 on an axis upward, until the eccentric means for permitting aninstallment or a re- Y secondary leg. When this movement has takenplace, the secondary leg may be con` veniently removed or placed inoperative position. It is of course necessary to remove or place'thetying means which holds the primary and secondary legs together. Aspreviously pointed out, the secondary leg is used during drillingoperations and when the drilling operations are over the secondary legisremoved in the manner just mentioned. After the secondary leg has beenremoved, the threaded bolt 58 is moved downwardin order that thehead-piece 49 and the crown structure maybe lowered. If it is desired toentirely remove the strain from the bolt 58, the crown structure may besupported bythe primary bearing member 34 in the following manner. Bysufficiently lowering the head-pieces49, the plate 50 thereof willengage upper faces 60 of the caps 39. The load is therefore trans ferredfrom they crown structure directly to the primary bearing member ratherthan by means of the eccentric equalizer 30. The secondary bearingmember 42 is preferably left in place so that it may be again usedwhenever desired.

Various modifications might `be made in the structure which I haveillustrated, and for this reason I do not wantrto be limited to thedetails shown. The equalizing means can be placedat the upper end of thederrick shown or can be placed adjacent to the base structure. Theeccentric equalizer member might be redesigned, and one of the primaryportions 33 and one of the fulcrum portions 31 might be removed. This`would leave an eccentric equalizer with but a single fulcrum portionand single primary and secondary portions relativelyV offset, as will beobvious. If this were done, obviously one of the fulcrum seats 52 andone of the'bearings 37 of the primary bearing member would be elim-Vinated. The threaded bolt 58 is not an indispensable part o f theinvention and may be eliminated if desired. It is quite useful, however,since it provides a simple operative moval of the secondary leg.

I claim as my invention: y l. In aderrick having a crown structure,

a base structure, and a double leg construction, the combination of: anequalizing means including an eccentric equalizer having a centraleccentric, intermediate fulcrums adapted to engage one of saidstructures, and outer eccentrics, said eccentrics engaging the legs ofsaid double leg construction.

2. In a derrick the combination of: a base structure; a crown structure;a double leg construction extending lfrom said base to said"` crownstructure; and an eccentric equalizer having a central eccentric means,engaging one leg of said double leg construction, an intermediatefulcrumengaging one of said structures, and outer eccentric means enstructures;and an equalizing means having -primary and secondary eccentric portionsenf gagingsaid bearings, and fulcrum portions combination of: a baseVengaging said fulcrum seats, in sucha'man- .Y

ner as to proportion the load on said primary and secondary legs. l l

4. In a'derrick the combination of: a base structure; a crownstructureya double legconstruction, including a primary anda sec-Vondary leg, extending between said struc-A,A tures; a pair of spacedand axially aligned..

primary bearings on said primary leg; a secondary bearing on saidvsecondary leg; a

pair of fulcrum seats von kone of said structures; and an oqualizingmeans having a'pair of relatively spaced primary "eccentric portionsengaging said primary bearings, a central secondaryv eccentric portionengaging said secondary bearing, and fulcrum lportions engaging saidfulcrum seats, in such a man ner as to proportion the load on saidprimaryV and secondary legs. f Y In testimony whereof, I have hereuntoset my hand at Los Angeles, California, this 30th day of December, 1930-Y LESLIE A. RAWSON;

